A new Shabbat-friendly technology, KosherSwitch, uses randomly timed light pulses to create various safeks, so that flipping the switch does not hallachically count as switching the light on, even in ...

Both the Torah and Gemarrah use math in various places, e.g. percentages (5ths (certain penalties); 10ths (ma'aser), etc.)
They also use many terms of measurements - e.g. shekel = 20 gerah; numerous ...

Regarding whether something needs to be considered chametz or not, there is a general rule of ראוי לאכילת כלב - i.e. - if a dog wouldn't eat it, then it's not considered food and therefore it is not ...

In the classic move Honey, I Shrunk the Kids and its sequels, people get shrunk down to 1/264th of their normal size. So, a person is around 1/4 of an inch tall.
If such a thing were even possible, ...

What Bracha acharona on .5 kezayit of grapes eaten together with .5 kezayit of mezonot crackers?
Do you say al hamichya ve'al haetz or is it boreh nefashot since neither is a kezayit?
Please provide ...

Some use a very wide gartel. A friend of mine mentioned an inyan (Judaism-sourced idea) that the gartel should be wider than one tefach. Can someone source this inyan that the gartel should be (more ...

Is there any source that says that in order to make a bracha for seeing e.g., a sage of Israel, a sage of the nations, or an unusual animal, one must be within four amos of the person/thing?
I found ...

I recently saw this story about students at YU who lit up their dorm windows to turn the entire building into a giant chanukia (just the form, not a real one). That inspired a question:
Exactly how ...

In recent centuries, authorities such as the Chazon Ish, Rabbi Chaim Na'eh, and Rabbi Moshe Feinstein ruled on the exact size of a tefach, ammah, kezayit, and other shiurim. What did people do before ...

Orach Chayim 211 is about what food to recite a blessing over (that is, and eat) first when one wishes to eat two foods. It's clear that (except according to the Rambam cited in 211:2) one does not ...

How much invalid material invalidates schach? (tefachim + inches preferred, but not required)
Would it make a difference if this material was in the middle of the roof, or on the side (=next to the ...

How large of a gap is allowed in a sukkah's schach (roof) without invalidating it? (in tefachim and inches/feet, if possible)
Would it make a difference if the gap was in the middle of the roof, or ...

I am wondering if small portions of dough, made by separate women in a challah baking class (thus each small portion would be owned by a single woman), can be combined to create the requisite amount ...

Inspired by Can too many decorations render a sukkah invalid?
If there is a big decoration hanging from the schach, is it OK as long as the top (part, or most of the decoration) is within 4 tefachim, ...

Someone told me that technically one needs to pour water on each hand only once since we use large quantities of water. Is there a halachic source for this?
I heard that the requirement to pour twice ...

I read somewhere (don't remember where) that the Chofetz Chaim used a kiddush cup that was a smaller shiur than he recommends to use in his Mishna Berurah.
Can anyone verify this and/or explain the ...

If you have an ikar (main) and tofel (secondary) mixture where the ikar is less than a kizayit but the entire mixture is greater than a kizayit, do you still make a beracha acharona on the ikar?
Or ...

If I recall correctly, it says somewhere that we each have a predefined number of words to speak, after which we die. (The idea being that one should be careful not to speak unnecessarily.)
Assuming ...

According to the OU, one must eat a minimum of "approximately 26 cubic centimeters" of Matza and Marror to fulfill his requirement (ie, a kezayis is 26 cm3). They also provide a chart, which states ...

The volume of Noah's Ark is 450,000 cubic cubits. The volume of the Ark of the Covenant is 5.625. Noah's Ark was thus exactly 80,000 times larger than the Ark of the Covenant. Is it significant that ...

I understand that a soul may be judged for a full 12 months after death but that we (generally) only say kaddish yatom for a parent for 11 months because the longest period is for the worst sinners ...

Since the miracle of the oil of Chanukah was that from one flask of oil they miraculously had enough oil for the menorah to burn all night for eight days, why did Chazal require us to light only for ...

I understand a bracha on dough is made if the amount of flour is greater than a certain amount, sourced here.
I have a small food processor I use to knead the dough. I plan to make a bunch of dough ...

The Gemara in Eiruvin 77a says that when a ten tefachim wall is between two courtyards, but is less than that to one courtyard (the floor of the courtyard is heigher), we give it to the one which is ...

When we make kiddush rabba with mezonos before having a real meal with bread, is there a shiur for how much mezonos a person should eat in order for it to be yotzei kiddush? Does it matter whether the ...

If a person for whatever reason momentarily has a thought which denies God, but then afterwards reaffirms his belief in Hashem, is that an act of kefira? Does a momentary lapse in belief constitute a ...